MAVEN Reconstructed SPK, NAV Solution, 2019-07-01 to 2019-10-01, Version 1 =========================================================================== Created by Boris Semenov, NAIF/JPL, Wed Oct 30 15:05:06 PDT 2019 Objects in the Ephemeris -------------------------------------------------------- This SPK file contains ephemeris data for the Mars Atmosphere and Volatile Evolution Mission (MAVEN) spacecraft. The NAIF ID code for MAVEN is -202. Approximate Time Coverage -------------------------------------------------------- This file covers the following part of the orbital phase of the MAVEN mission (orbits 9417 through 10023): Start of Interval (ET) End of Interval (ET) -------------------------------- -------------------------------- 2019 JUL 01 00:01:09.184 2019 OCT 01 01:01:09.182 Status -------------------------------------------------------- This file was created by merging regular reconstructed OD solution SPK files produced by the MAVEN NAV team during the orbital phase of the mission. This file was created by NAIF for archiving in the Planetary Data System (PDS). Pedigree -------------------------------------------------------- The original SPK files used to create this file contained only reconstructed trajectory. They were officially delivered to the MAVEN project data base by the MAVEN NAV team. The list of the original files data from which has been merged into this file is provided in Appendix 1 of these comments. Segment Boundary Discontinuities -------------------------------------------------------- This SPK file contains a large number of SPK segments that came from original individual SPK files. Although, each segment provides continuous trajectory within the interval that it covers, in general a position and velocity discontinuity exists at the boundary of the segment and the segments whose coverages immediately precede or follow it. The times and magnitudes of these discontinuities are provided in Appendix 2 of these comments. Usage -------------------------------------------------------- This file should be used together with DE430 planetary ephemeris and MAR097 satellite ephemeris since the original SPK files contained subsets of these particular ephemeris in them. Contacts -------------------------------------------------------- If you have questions regarding this data contact Boris V. Semenov (818)-354-8136 Boris.Semenov@jpl.nasa.gov Appendix 1: Original SPK List -------------------------------------------------------- The original SPK files, the data from which has been included into this file, are: trj_orb_09417-09474_rec_v1.bsp trj_orb_09473-09519_rec_v1.bsp trj_orb_09518-09562_rec_v1.bsp trj_orb_09561-09613_rec_v1.bsp trj_orb_09612-09659_rec_v1.bsp trj_orb_09658-09700_rec_v1.bsp trj_orb_09699-09742_rec_v1.bsp trj_orb_09741-09773_rec_v1.bsp trj_orb_09772-09843_rec_v1.bsp trj_orb_09842-09889_rec_v1.bsp trj_orb_09888-09924_rec_v1.bsp trj_orb_09923-09982_rec_v1.bsp trj_orb_09981-10028_rec_v1.bsp Appendix 2: Segment Boundary Discontinuity Summary -------------------------------------------------------- This SPK file contains a large number of SPK segments that came from original individual SPK files. Although, each segment provides continuous trajectory within the interval that it covers, in general a position and velocity discontinuity exists at the boundary of the segment and the segments whose coverage immediately precede and follow it. The times and magnitudes of these discontinuities are provided in the table included in this Appendix. The top portion of the table contains the name of this SPK file. All descriptive lines in the top portion of the file start with the ``#'' character to allow direct plotting of the data in the freeware ``gnuplot'' application. The table consists of 5 columns. The first column is the orbit number within which a segment boundary with discontinuity occurs. The next column contains the UTC time of that segment boundary. The last three columns (3..5) contain view coordinate frame components -- ``down track'' (this direction is parallel to the velocity vector), ``normal to plane'' (this direction is computed as cross product of position vector by velocity vector) and ``in plane'' (this direction is computed as a cross product of ``down track'' by ``normal to plane'') -- of the difference between the state vectors computed at that UTC time defining segment boundary at which a discontinuity exists. The pairs of segments and discontinuity times are determined using an algorithm that emulates the standard SPK loading priority -- ``last loaded segment takes precedence''. Therefore, the discontinuities summarized in the file are those which a user reading file would actually see. The difference components in the view coordinate frame were computed for each discontinuity using the following algorithm: -- A single state was computed from each pair of segment the J2000 frame at the time of discontinuity. -- For this pair of states, a position difference vector was computed by subtracting the state computed from the segment with higher priority from the state computed from segment with lower priority. Then, a frame transformation matrix rotating these difference vectors from J2000 to the view coordinate frame defined by the state obtained from the higher priority segment was computed, and the position difference vector was rotated to the view frame coordinates using this matrix. The segment boundary discontinuities for this file are: # # Summary of discontinuities at segment boundaries for # SPK file ./maven_orb_rec_190701_191001_v1.bsp, km: # #ORBNUM BOUNDARY TIME (UTC) DOWNTRK INPLANE NORMAL #------- ----------------------- ------- ------- ------- 9417 2019-07-01T00:33:50.815 0.002 -0.001 0.044 9428 2019-07-02T16:33:21.815 0.003 -0.001 0.031 9430 2019-07-03T00:33:51.815 0.000 -0.000 0.003 9440 2019-07-04T13:05:09.815 -0.004 0.002 -0.021 9449 2019-07-05T21:28:50.816 -0.000 0.000 -0.002 9458 2019-07-07T07:53:50.816 0.002 0.000 -0.003 9463 2019-07-08T00:26:50.816 -0.003 0.001 -0.012 9473 2019-07-09T15:25:48.816 -0.002 -0.001 0.006 9483 2019-07-11T02:24:34.816 -0.002 0.001 -0.003 9495 2019-07-12T21:47:19.816 0.002 -0.001 0.006 9500 2019-07-13T17:33:50.816 -0.001 -0.000 0.001 9509 2019-07-15T00:53:50.816 0.000 0.000 0.001 9518 2019-07-16T11:33:50.816 -0.006 -0.002 0.007 9528 2019-07-17T21:58:50.816 0.006 -0.002 0.013 9539 2019-07-19T16:18:50.816 -0.014 -0.005 0.012 9551 2019-07-21T10:58:50.816 0.017 -0.003 0.020 9561 2019-07-22T23:38:50.816 0.002 -0.000 0.002 9565 2019-07-23T13:53:50.816 0.022 -0.006 0.032 9575 2019-07-25T01:32:50.816 -0.013 0.005 -0.018 9585 2019-07-26T15:19:50.816 0.001 -0.000 0.001 9591 2019-07-27T11:58:50.816 0.012 -0.004 0.014 9601 2019-07-29T00:28:50.816 0.036 -0.013 0.037 9612 2019-07-30T17:44:56.816 0.085 -0.011 0.092 9620 2019-07-31T23:29:56.640 0.220 0.032 0.150 9624 2019-08-01T14:28:46.081 -0.134 -0.042 -0.043 9633 2019-08-02T23:30:12.816 -0.043 -0.016 -0.007 9637 2019-08-03T13:15:12.816 -0.046 -0.000 -0.043 9641 2019-08-04T02:35:13.816 0.075 -0.030 0.063 9650 2019-08-05T12:40:14.816 0.042 0.001 0.038 9658 2019-08-06T16:33:50.816 0.007 -0.003 0.005 9667 2019-08-08T01:58:50.816 -0.019 0.006 -0.020 9681 2019-08-10T05:17:50.816 -0.217 0.039 -0.209 9691 2019-08-11T16:45:50.816 -0.139 0.053 -0.031 9699 2019-08-12T23:08:50.817 0.003 -0.000 0.002 9709 2019-08-14T10:18:50.817 -0.001 0.000 0.000 9717 2019-08-15T16:33:50.817 0.030 -0.003 0.025 9730 2019-08-17T14:58:50.817 -0.009 0.003 -0.002 9741 2019-08-19T07:25:21.817 -0.059 0.021 -0.031 9754 2019-08-21T07:45:12.817 -0.012 -0.001 -0.010 9764 2019-08-22T19:10:12.817 0.070 -0.025 0.026 9772 2019-08-24T00:38:09.817 0.068 -0.015 0.037 9785 2019-08-25T23:43:13.817 0.020 -0.006 0.006 9795 2019-08-27T11:45:50.817 -0.052 0.021 0.008 9805 2019-08-29T00:22:42.436 0.036 -0.012 0.001 9817 2019-08-30T20:03:15.306 0.051 -0.018 -0.004 9829 2019-09-01T15:43:41.700 -0.070 0.026 0.012 9835 2019-09-02T14:50:13.817 0.138 0.031 0.103 9842 2019-09-03T14:58:50.817 0.009 -0.005 -0.003 9851 2019-09-04T23:58:50.817 0.065 -0.019 -0.010 9863 2019-09-06T19:28:50.817 -0.010 0.006 0.005 9877 2019-09-08T22:28:50.817 -0.020 0.006 0.010 9888 2019-09-10T14:33:50.817 -0.011 0.004 0.006 9897 2019-09-12T00:23:50.817 0.051 0.011 0.026 9910 2019-09-13T22:00:50.817 0.019 -0.008 -0.024 9917 2019-09-15T00:08:50.817 -0.122 0.029 0.076 9923 2019-09-15T21:43:50.817 -0.016 0.005 0.016 9935 2019-09-17T18:20:02.678 -0.046 -0.007 -0.006 9943 2019-09-18T21:55:16.817 0.019 -0.008 -0.031 9955 2019-09-20T19:08:50.817 -0.023 -0.005 -0.004 9969 2019-09-22T21:13:50.817 -0.013 0.002 0.014 9981 2019-09-24T16:55:31.817 -0.001 -0.000 0.002 9990 2019-09-26T00:27:40.817 0.004 -0.002 -0.010 10003 2019-09-27T23:13:50.817 0.005 -0.001 -0.003 10011 2019-09-29T06:58:50.817 -0.021 -0.009 -0.031 10016 2019-09-29T22:38:50.817 0.003 -0.001 -0.007 End of comments.